Before the advent of computers, the assimilation and interpretation of information required extensive manual data collection as well as error-prone hand calculations carried out by many individuals. The manual tabulation of large quantities of data typically resulted in a small percentage of errors in the collected data. Furthermore, additional errors had been introduced through the use of laborious manual numerical analyses. Although the adoption of accountant's columnar pads to create paper spreadsheets eased the assimilation of data and reduced the error propagation, the manual preparation of such spreadsheet was rather tedious error prone to calculation errors, and expensive in labor.
The advent of personal computers brought forth electronic spreadsheets such as VISICALC, LOTUS-1-2-3, EXCEL and QUATRO-PRO and databases such as D-BASE, VISUAL FOX-PRO and ACCESS which provide convenient systems for quickly organizing information. As discussed in U.S. Pat. No. 5,502,805, entitled "SYSTEM AND METHODS FOR IMPROVED SPREADSHEET INTERFACE WITH USER-FAMILIAR OBJECTS", typical spreadsheet programs configured the memory of the computer to resemble the column/row or grid format of an accountant's columnar pad, thus providing a visible calculator for a user in each cell of the column/row format. To communicate the location of the cell, a common scheme assigned a number to each row in the spreadsheet and a letter to each column. Thus, the cell represented the basic addressable storage location of the spreadsheet at each intersection of a row with a column. In addition to holding text descriptions and numeric data, each cell can store formulas or special instructions specifying calculations to be performed on the numbers stored in the cells. Upon receipt of new data, the formulas were automatically updated to support "what if" scenarios.
Computerized spreadsheets offered many advantages over the old pen-and-paper approach. For one these spreadsheets were capable of supporting very large spreadsheets that would be unwieldy to maintain by hand. Further, the computerized spreadsheets were capable of supporting scenario calculations where the entered information may be quickly recalculated with different assumptions. Thus, these computerized spreadsheets offered dramatic improvements in ease of creating, editing and applying mathematical models such as financial forecasting. Similarly, databases allowed users to maintain vast quantities of data and to manipulate the information via query commands. Thus, the usefulness of spreadsheets, databases and other business applications made them staple software for data summary, advanced numerical analysis and charting applications.
Although computerized spreadsheets and databases offered significant productivity gains in modeling complex data, none was as intuitive to use as the old, but familiar paper and pencil. To use the new technology, the user had to type information into the cells of the spreadsheet. In the hand of inexperienced users, the data entry aspect was unpleasant. Further, the verification for correct data entry was time consuming. Additionally, the user had to master many complex and arbitrary operations. For example, to find the proper commands, the user needed to traverse several nodes of a menu. Advances in computer technology had not simplified life for users, since these advances have been largely employed to build more complex functions and modeling capability into the spreadsheet with even more menus and sub-menus. Since the alternative of perusing through a staggering array of incomprehensible icons was not also palatable to users, most users only used a fraction of the available commands and features. Furthermore, conventional computerized spreadsheets and databases still required users to manually enter the information.
Additionally, applications such as spreadsheets, databases, project planning tools and CAD/CAM systems required large display areas to quickly and conveniently interact with users. However, portable computing appliances must balance the conflicting requirements of the readability of the displayed characters and the size of their display screens. On one hand, the portability requirement implied that the screen be small. On the other hand, the readability requirement pushed in the opposite direction and dictated that the display area be as large as possible. However, as computing appliances with large screens consumed more power, were more fragile, expensive and bulkier, most portable computers offered only a small display surface. The selection of a small display size restricted the user into making undesirable choices between displaying either larger characters or mote information. For busy executives, attorneys, doctors and other professionals, such restrictions were impractical. Thus, the display system need to be portable, cost effective, and easy to use in comparison with the pen and paper approach before the conventional pen and paper method can be replaced.
In addition to being as easy to use as the pen and paper approach, the portable computing appliance needed to provide information integration advantages, including the ability to capture data from scanners, barcode readers, or the Internet, over the cheaper pen and paper approach to further justify the expense associated with such electronic computer systems. Furthermore, as portable computers are typically deployed in field applications by service providers where employees are scattered over a wide geographic area, the information advantages arising from integrating data associated with a global positioning system (GPS) are needed in the management and control of field personnel to ensure that the employees are actually at the respective expected locations. Additionally, an ability to link information generated at the client's site with follow-up discussions and letters necessary to close the transaction is needed to enhance the efficiency of field personnel.